Common Name:Atlantic Oyster Drill, American Tingle, American Whelk Tingle

Species Description:
The shell of Urosalpinx cinerea is knobby having rugged whorls (turns of
the shell) with rounded shoulders usually numbering 5. Each complete turn of
the Atlantic oyster has 9-12 vertical, rounded ribs crossed with 15 rows of
thinner spiral ridges. The aperture (opening through which the snail moves in
and out of the shell) of U. cinerea is oval with an open canal at the
base. Shells are usually yellow sometimes orange, grey or white and
occasionally bearing brown streaks. The interior of the shell can be purple,
red-brown or yellow. The operculum (the plate that closes to protect the snail
when it is inside its shell) can be orange or yellow-brown.

U. cinerea, a mollusk in the family Muricidae, is considered a major
pest among the world's bivalve fisheries (Robinson and Dillon 2008). In colder
waters, this species will be dormant throughout the winter and emerge in April
to feed (Franz 1971).

II. HABITAT AND DISTRIBUTION

Regional Occurrence:
The natural range of Urosalpinx cinerea is northwestern Atlantic to
southeastern Florida. The mode of development of U. cinerea naturally
limits its population range (Minchin 1996). Human transport in ballast water
of ships and in seed beds of its bivalve prey have introduced this voracious
muricid gastropod to the Gulf of Mexico, the Pacific coast of the United
States, and the eastern north Atlantic (Robinson and Dillon 2008). The
Atlantic oyster drill occurs in intertidal and shallow subtidal waters in
estuaries and bays to a maximum depth of approximately 15 m and is common on
rocks and oyster reefs (Franz 1971).

IRL Distribution:Urosalpinx cinerea inhabits oyster reefs (Crassostrea virginica) of the Indian River Lagoon.

III. LIFE HISTORY AND POPULATION BIOLOGY

Age, Size, Lifespan:Urosalpinx cinerea live 5-8 years and reach sexual maturity in 2 years
when they reach approximately 16mm in length. The shell size of the Atlantic
oyster drill is reported to vary among populations (Franz 1971). Populations
in England are reported to be larger than the eastern Atlantic. On the
Pacific coast, this gastropod is recorded to grow to 30-35 mm in length. In
this same population, female specimens were recorded at larger sizes than
their male counterpart. Variation in growth rate, span of time during
growth, and diet may account for these observations (Franz 1971).

Reproduction:Urosalpinx cinerea spawns in spring and summer. Each female attaches
approximately 20-40 leathery vase-shaped egg capsules to a hard surface. The
capsule is transparent and half of centimeter in height (Franz 1971, Robinson
and Dillon 2008).

Embryology:
Atlantic oyster drill eggs develop directly into benthic juveniles, skipping a
pelagic stage (Robinson and Dillon 2008). Newly emerged juveniles migrate to
their food source. In a mid-Atlantic population, first season specimens were
reported to associate closely with ectoprocts (Franz 1971). Most shell growth
in Urosalpinx cinerea occurs in the first two seasons before the snail
matures.

IV. PHYSICAL TOLERANCES

Temperature:
The optimal temperature for the development of the Atlantic oyster drill is
reported to be 20°C (Ganaros 1958). In laboratory experiments, Urosalpinx
cinerea were shown to feed optimally at 25°C and exhibited significant
decreases as the temperature increased or decrease (Hanks 1957). In addition,
temperature fluctuation has a profound effect on the development. When
temperatures are decreased below 25°C , an increase in the number of days it
takes early larvae to attain the shelled veliger stage is observed (Ganaros
1958). However, temperature fluctuations did not inhibit the ability of the
larvae to attain the protoconch stage.

Salinity:Urosalpinx cinerea can live in salinities as low as 13 - 15‰. In
populations of the Atlantic oyster drill collected from the James River,
Virginia, mortality was observed when the salinity decreased to 9‰ (Zachary and
Haven 1973). When the salinity was increased the activity of the oyster
drills also increased. In laboratory experiments examining the combined
effects of temperature and salinity, increased temperatures resulted in
increased feeding and reproduction even at very low salinities (Manzi 1970).

V. COMMUNITY ECOLOGY

Trophic Mode:
The Atlantic oyster drill preys upon oysters, barnacles and other bivalves
including mussels. Young snails feed on bryozoans, ectoprocts, small snails
and barnacles. In San Francisco Bay, the preferred prey is reported to be
young barnacle and clams. In the mid-Atlantic, the barnacle Balanus balanoides
and the mussel Mytilis edulis are the preferred prey (Franz 1971).
Adults are reported to use a chemical cue released from the prey to locate
suitable feeding habitats (Ritchoff et al. 1983). In laboratory experiments
with newly hatched juveniles that were not previously exposed to prey species,
Urosalpinx cinerea preferentially migrated upstream toward "odors" from
living barnacles.

The gastropod bores a hole through the shell of its prey with a file-like
rasping organ called a radula and produces acidic chemical secretions from a
boring gland that soften the shell. U. cinerea then insert its
proboscis to get to the prey's soft tissue (Brusca and Brusca 1990). The
Atlantic oyster shell is a voracious predator and has the potential to be one
of the most destructive predators of young oysters (Ganaros 1958).

Competitors:
Competitors of the ornate blue crab are other crustaceans, in particular C.
sapidus and C. similis.

INVASION INFORMATION

Invasion History:Urosalpinx cinerea is an invasive species in many parts of the world, and has been introduced to
several new regions by human transport by ship and other means. It
was first found on the Pacific coast of the United States and Canada in the
late 1800's introduced in shipments of imported Crassostrea virginica.
The American oyster drill was introduced to the United Kingdom in shipments of
C. virginica at the turn of the century. In this region, it has been
reported from Essex and Kent in southeast Britain (Faasse and Ligthart 2007).
Tributyltin (TBT) has been an effective control in the southeast Britain
populations causing imposex in the females, a maculizing syndrome inhibiting
reproductive processes (Gibbs et al. 1991). More recently following the ban of
TNT in 1993, U. cinerea was reported from The Netherlands. It is
suspected that U. cinerea may have been introduced in seed mussels
imported from Sussex and Kent.

Invasion History:Urosalpinx cinerea poses a major concern because they usually thrive in
their new habitat without specialized predators and parasites (Faasse and
Ligthart 2007).

Invasion History:
Damage to the oyster bed fisheries around the world has been estimated to be in
the millions of dollars per year (Manzi 1970).

Ganaros AE. 1958. On developments of early stages of Urosalpinx cinerea
(Say) at constant temperatures and their tolerance to low temperatures.
Biological Bulletin 114:188-195.

Gibbs PE, Spenser BE, and PL Pascoe. 1991. The American oyster drill,
Urosalpinx cinerea (Gastropoda): Evidence of decline in an
imposex-affected population (R. Blackwater, Essex). Journal of the Marine
Biological Association of the United Kingdo, Plymouth. 71:827-838.